Conventional speaker apparatuses include one that is disposed with multiple speaker units driven by a common acoustic signal in the same housing, includes multiple phase adjustment circuits, which are related to the speaker units, and can control the directional characteristics of the speaker apparatus by adjusting delay amounts of the acoustic signal among the speaker units (e.g., Patent Literature 1).
By installing such a speaker apparatus in an acoustic space such as a concert hall or a conference room, and appropriately adjusting the delay amounts for the respective speaker units, the directional characteristics of the speaker apparatus can be controlled so as to make a specific area in the acoustic space serve as a listening target area. However, there is a problem that it is not easy to designate the delay amounts for the respective speaker units such that the directional characteristics of the speaker apparatus correspond to a desired listening target area.
The delay amounts of the speaker units must be determined on the basis of the relative positional relationship between the speaker apparatus including the direction of the speaker apparatus and the listening target area. In addition, the listening target area is not necessarily an area on a horizontal plane, or the speaker apparatus is not necessarily arranged on the same plane as the listening target area. For these reasons, it is necessary to specify the relative positional relationship between the speaker apparatus and the listening target area as a positional relationship in a three-dimensional space, and therefore it is not easy to determine the delay amounts for the respective speaker units.
In particular, at the site where the speaker apparatus is installed, determining the delay amounts for the respective speaker units is not easy. For example, it is not easy to determine how much the listening target area deviates from the front direction of the speaker apparatus. For this reason, a method that before installing the speaker apparatus, envisages the relative positional relationship between the speaker apparatus and the listening target area to preliminarily determine the delay amounts for the respective speaker units is possible. However, in the case of employing such a method, if the actual installation position and direction of the speaker apparatus in the acoustic space are different from a preliminarily envisaged position and direction, there arises a problem that the directional characteristics of the speaker apparatus do not correspond to a desired listening target area.